Monday 1 March 2021

The USSR's Hungriest Tank

Comparative trials of four Soviet tanks were conducted in the summer and fall of 1976 according to order of the Minister of Defense of the USSR D.F. Ustinov titled "On military trials of tanks" issued on July 20th, 1976. In September, a summary titled "Minutes of trials results" was composed. This article will discuss the contents of these documents.

The T-80 is a polarizing tank. Its supporters grow in number day by day, but most have seen it only on the screen, or at best at a museum or a demonstration. Fewer people consider the T-80 an unnecessary and harmful vehicle, but those are usually professionals with a deeper understanding.

T-80 tank.

Even those with experience fall on both sides of the divide. Enlisted men and junior officers are typically thrilled with the tank. Indeed, it is easy to handle and service, and is quite forgiving on the driver. The engine is easy to start even in winter, one doesn't have to put on their oil-soaked overalls and mess around in the engine compartment. Those who serve in these tanks like to think of themselves as the elites of the tank forces. The opinion of senior commanders who need to think about battle readiness of their units and supply headaches is usually different.

Everyone knows that the T-80s gas turbine is a fuel hog. Some voice this opinion loudly, others conceal or circumvent the issue for whatever reason. This frequently causes discussions: sure, the T-80 needs a lot of fuel, but how much? To answer this question, let us turn to original documents: reports on trials of T-80, T-62, T-72, and T-64A tanks held in mid-1976. These trials were ordered by Minister of Defense D.F. Ustinov on the day after the T-80 was accepted into service.

T-80 tank model 1976. Photo by M. Pavlov.

It's hard to say that the results of these trials are unknown. They were often described in literature dedicated to the creation of the second generation of post-war tanks. Four quite modern and serious books come to mind, in addition to innumerable articles in periodicals. Their authors, tank designers from Leningrad and Nizhniy Tagil, are often true patriots of their design bureaus and creations, and thus cannot be trusted to remain objective. However, times goes by, and archive documents are declassified, and we can finally look at the primary documents ourselves.

The Commander in Chief of the Land Forces was ordered to perform trials on the territory of the Belorussian, Kiev, and Carpathian Military Districts between August 20th and September 30th, 1976, in order to compare the combat, technical, and usage characteristics of the T-80, T-64A, T-72, and T-62 tanks in identical conditions in order to use this information to improve the tanks further.

T-80 tanks at the Kirov Factory in Leningrad.

A special battalion composed of four companies of ten tanks each was formed in the Kiev Military District in order to conduct the trials. Cohesion building exercises including at least 300 km of driving were scheduled before the trials.

The trials evaluated tactical capabilities of each company, their ability to drive in combat and travel formations at daytime and at night, the time spent getting ready for battle after a lengthy march. Crew comfort, expenditure of lubricant and fuel, time to refuel, cruising range using main and drop tanks, and time spent on maintenance were also recorded. The difficulty in readying tanks to ford rivers was measured separately.

Trials 2500-3000 km long were held in the Belorussian, Carpathian, and Kiev Military Districts. The trials consisted of daily marches at least 300 km long, company level tactical exercises with and without battle drills, firing of all available types of ammunition from standstill and on the move, fording a river, and exercises from tank driver training courses.

T-80 tank company on trials. Photo by M. Pavlov.

Officers and crews from the 213th Motorized Rifle Division of the Volga Military District were used to crew the T-80 tanks. Crews for the T-64A and T-64B tanks arriving from the Malyshev factory (including three with the "Cobra" missiles) came from the Kiev Military District. T-72 tanks from Nizhniy Tagil were crewed by troops from the Belorussian Military District. Finally, the T-62 tanks came from the 969th Central Reserve Base in Urechye (near Minsk), their crews were from the Kiev Military District. The battalion went through cohesion exercises from August 10th to August 19th. Each tank drove for 240-280 km.

The results of the trials were combined into a final report. The report stated that the military trials confirmed that Soviet tanks had high battle and usage characteristics and met modern requirements. The T-80 was superior overall (effectiveness of armament, mobility, battle readiness, crew comfort, communication, service), but fell behind the T-72, T-62, and T-64A when it came to cruising range and fuel economy.

The T-64B with its automatic fire control system and guided munitions was superior to tanks of other types when firing at a range of 4000 meters.

Photo taken at the trials held in the Belorussian Military District, 1976. Photo from the Uralvagonzavod museum.

It was decided to retain the current direction of Soviet tank building and continue developing the following:
  • Introduction of a high precision automatic fire control system.
  • Introduction of guided munitions.
  • Increase of firing precision and firepower.
  • Increase of ammunition capacity.
  • Improving visibility and target acquisition, especially for the commander.
  • Increase in effectiveness of protection, including development of new types.
  • Further increase in the power to weight ratio of the tank in combination with improving the efficiency of the transmission, running gear, and controls.
  • Increasing fuel economy and cruising range of tanks.
  • Closing the gap between the current level of communications and modern requirements for controlling tank units.
It was desirable to develop a single tank with a gas turbine or diesel engine that combined the best technical solutions of the T-80, T-64B, and T-72.

At the proving grounds in the Belorussian Military District, 1976. Photo from the Uralvagonzavod museum.

Trials revealed the need to continue work on improving certain characteristics and unifying the T-80, T-64A, T-64B, T-72, and their equipment as much as possible. Trials also confirmed that it is necessary to modernize the T-62, in part to improve the effectiveness of its armament, by installing the "Volna" fire control system with a quantum rangеfinder and ballistic computer.

The T-64B equipped with a tank rangefinder, ballistic computer, and high precision stabilizer showed superior results compared to the T-80 and T-72: 1.33 and 1.76 times faster target destruction respectively, 1.2 and 1.8 times less ammunition used respectively.

Aside from the T-64B, the T-80 displayed highest results in nearly all gunnery trials. The supremacy of the T-80 over the T-72 with the same armament could have been the consequence of a better suspension, smoother changes in speed, and less vibration when the engine was running.

The T-72 and T-64A were nearly equal in hit rate, ammunition expenditure, and time to strike a target despite different sight systems (TPD-K1 and TPD-2-49). This was because the T-64A conducted a significant amount of trials alongside the T-64B equipped with a quantum rangefinder, and thus could correct their fire using data obtained from the T-64B tanks. The drop in T-72 performance could have been caused by a lack of experience in using the TPD-K1 quantum rangefinder.

The T-62 showed the worst results, which are explained by inferior ballistics of the 115 mm U5-TS gun, high sensitivity of the HEAT ammunition to side winds, and inferior fire control systems.

The maximum effective engagement distance for tanks with 125 mm guns was 2300-2500 meters with APFSDS from standstill or 1700-1900 on the move, 1600-1800 with HEAT from standstill or 1400-1600 meters on the move. The T-62's range was less than that of the T-80, T_64A, and T-72 by 200-300 meters.

The T-64B firing the 9M112 round at 2900-3800 meters showed that tanks with the "Cobra" system have superior range and can strike the target reliably on the move or from standstill. Out of 29 shots 21 hit, 4 missed, and 4 misfired. The presence of misfires indicated that work on improving the reliability of ammunition was still necessary.

Firing HE at a large distance showed that tanks can combat small targets, including ATGM-equipped vehicles, at ranges of 3500-4000 meters. On average, platoons shooting at targets from a long range expended the following amount of time and ammunition:
  • T-80: 5.4 rounds in 1.20 minutes
  • T-64A tanks: 6.3 rounds in 1.50 minutes
  • T-72 tanks: 7.6 rounds in 1.75 minutes
  • T-62 tanks: 6.0 rounds in 2.60 minutes
Odds of scoring a hit on the first shot at 1200 meters from a standstill or 1200-1300 meters while moving against a #12 target with APFSDS was measures as follows:
  • Standstill:
    • T-80, T-64A, T-64B, T-72 tanks: 95%
    • T-62 tanks: 100%
  • On the move:
    • T-80, T-64A, T-64B, T-72 tanks: 87-93%
    • T-62 tanks: 73%
During training shoots, the following hit rates were recorded:
  • T-80: 54%
  • T-64A: 48%
  • T-72: 44%
  • T-62: 34%
The time to prepare the first shot was as follows:
  • T-80: 20-27 seconds
  • T-64A: 20-35 seconds
  • T-72: 22-29 seconds
  • T-62: 18-28 seconds
Time spent to defeat the target:
  • T-80: 42 seconds
  • T-64A: 51 seconds
  • T-72: 54 seconds
  • T-62: 75 seconds
Gunnery trials showed that the weapons and ammunition were sufficiently reliable to carry out all trials. The guns did not need to be recalibrated or serviced after lengthy marches. It took 10-15 minutes to prepare for battle after a long march, mainly for external inspection and dusting of the weapons, sights, and observation devices.

A T-80 tank traversing a ruined road during trials.

The trials showed that the T-80, T-64A, and T-72 have high tactical characteristics and could move out, form into pre-battle and battle formations, attack, maneuver, flank, and defeat concealed targets at high speeds. Company level tactical exercises with battle drills gave the following average rate of advance:
  • T-80: 14.1 kph
  • T-64A: 12.4 kph
  • T-72: 13.2 kph
  • T-62: 11.4 kph
Despite the slightly higher rate of advance, the T-72 showed worse gunnery results than the T-64A. The T-62 had the poorest rate of advance and percentage of targets hit. The hit rate was as follows:
  • T-80: 63.6%
  • T-64A: 37.3%
  • T-72: 36.1%
  • T-62: 19.6%
And the average amount of defeated targets:
  • T-80: 81.5%
  • T-64A: 60.0%
  • T-72: 66.7%
  • T-62: 66.1%
A column of T-80 tanks driving on Ukrainian roads. Photo by Spetsmash Ltd.

In driving during the day on dirt roads, the following speeds were maintained:
  • T-80: 32.1-40 kph
  • T-64A: 26.0-29.8 kph
  • T-72: 28.8-35.6 kph
  • T-62: 20.8-25.7 kph
The average tactical speed did not differ much from average technical speed. The T-80 company showed the best speed while driving, and this was not the limit. It was estimated that if controls and observation devices for the commander and driver are improved, this speed can rise significantly.

The average speed in a column recorded during training was (travel/battle formation):
  • T-80: 28.2/25.5 kph
  • T-64A: 23.7/19.9 kph
  • T-72: 26.2/23.0 kph
  • T-62: 20.0/16.8 kph
A daily march of 300 km took the following amount of time:
  • T-80: 10.5-11 hours
  • T-64A: 13.5-14 hours
  • T-72: 12.0-12.5 hours
  • T-62: 16.5-18 hours
Considering the time necessary for service and rest, the following distances could be covered daily by each company:
  • T-80: 400-450 km
  • T-64A: 300-330 km
  • T-72: 350-400 km
  • T-62: up to 270 km
On average, over the course of the trials each tank expended:
  • T-80: 22,820 L of fuel and 0 L of oil
  • T-64A: 13,544 L of fuel and 304 L of oil
  • T-72: 12,337 L of fuel and 157 L of oil
  • T-62: 9,782 L of fuel and 134 L of oil
Per 100 km, average fuel expenditure was as follows:
  • T-80: 642 L
  • T-64A: 404 L
  • T-72: 357 L
  • T-62: 308 L

A T-80 tank fording a river. Photo by Spetsmash Ltd.

Trials showed that the average cruising range for each tank was (main tanks/drop tanks/while maintaining a 20% reserve):
  • T-80: 278/338/270 km
  • T-64A: 305/400/320 km
  • T-72: 322/430/344 km
  • T-62: 301/427/341 km
The range of average cruising range in varying road conditions was as follows (main tanks/drop tanks):
  • T-80: 255-340/310-413 km
  • T-64A: 263-366/348-490 km
  • T-72: 273-400/366-535 km
  • T-62: 256-358/363-506 km
The T-64A, T-72, and T-62 carried enough oil to drive for two days without refilling. The T-80's oil supply was effectively limitless.

Discussion of trials results, 1976. Uralvagonzavod museum.

The time to refuel one tank was as follows:
  • T-80: 18 minutes
  • T-64A: 30 minutes
  • T-72: 27 minutes
  • T-62: 26 minutes
Three fuel trucks took the following amount of time to refuel a tank company:
  • T-80: 40-44 minutes
  • T-64A: 64-68 minutes
  • T-72: 60-64 minutes
  • T-62: 56-60 minutes
The report noted that the T-80's pressurized central refueling system significantly reduced refueling time, made refueling convenient, and protected the fuel from dirt and dust.

Crew conditions were judged to be satisfactory. The crews of T-80, T-64A, T-72, and T-62 tanks were capable of carrying out further missions even after length marches. Medical evaluation of the crews showed that the T-80's crews were the least exhausted, the T-72 and T-64A crews were slightly more exhausted, and the T-62 crews were the most exhausted.

Investigation of battle readiness drills carried out during the trials showed that units with T-80, T-64A, T-72 and T-62 tanks were capable of quickly moving out to battle. The time to depart from the base in warm weather was as follows:
  • T-80: 5.5 minutes
  • T-64A: 10 minutes
  • T-72: 10 minutes
  • T-62: 12 minutes
Including technical inspection, refueling, loading ammunition, repairs and adjustments, maintenance time after a long march took up to 4.5 hours for units equipped with T-80, T-64A, and T-72 tanks, and up to 6.5 hours for units with T-62 tanks.

The time taken to prepare a tank for fording a river was as follows:
  • T-80: 84 minutes
  • T-64A: 27.9 minutes
  • T-72: 21.3 minutes
  • T-62: 25.4 minutes
The average movement speed of T-80, T-64A, T-72, and T-62 tanks when crossing obstacles was 9-13 kph. On a road with obstacles, the following average speeds were recorded: 
  • T-80: 31.2 kph
  • T-64A: 26.4 kph
  • T-72: 28.5 kph
  • T-62: 19.2 kph
Compared to the T-62, the T-80, T-64A, and T-72 were much easier and faster to service due to shorter maintenance tasks carried out more frequently. The T-80 was the fastest to service, the T-64A was the slowest. The total amount of time it took to service one tank over 1000 km of driving was:
  • T-80: 8.16 hours
  • T-64A: 11.06 hours
  • T-72: 13.03 hours
  • T-62: 22.12 hours
The T-80's monobloc power pack and removable road wheel disks allowed the crews to replace the power pack in just 4-5 hours and a road wheel in 0.5 hours.

None of the tanks tested had a troubleshooting system, which made finding and correcting issues time consuming. Only the T-64B had a troubleshooting feature in the "Cobra" fire control system. Tanks worked reliably during trials, with the exception of five GTD-1000T engines that broke down due to manufacturing defects.

Chief Designer of the Spetsmash SKB design bureau N.S. Popov gives instructions to T-80 tank crews. Photo by Spetsmash Ltd.

The T-80 was awarded first place as a result of the trials. However, the readers can make their own conclusions. It is important to know the context for the trials. The commission needed to justify the acceptance of a third MBT into service, as the interests of the "Transmash" design bureau and the Kirov factory were represented by D.F. Ustinov personally. Chief Designer N.S. Popov also joined the Central Review Commission of the KPSS in 1976 and the Central Committee of the KPSS in 1982.

Various tricks were obtained to get the necessary results. For instance, T-72 gunners never worked with laser rangefinders before, and the T-64A tanks were assisted by T-64B tanks, which should not have been at the trials to begin with. These factors are stated in the report and don't have anything to do with the T-80 directly. However, participants recall that the T-80 tank columns spread out over the length of several kilometers during marches to obtain higher speed and fuel economy results. This was effectively no longer a column, but an array of individual tanks, where each one drove in whatever mode was the most suitable. Even without knowing these nuances, it is not hard to see that the T-80 did not surpass its competitors by that much, especially the T-72. In real combat, the benefits of these advantages would be negligible.

The fuel consumption of the T-80 tank was indeed catastrophically high. It took 642 L of fuel to drive 100 km compared to the T-72's 357 L. The average fuel expenditure for one T-80 was 22,820 L, but only 12,337 L per T-72. Of course, the T-80 "flew" on a 1000 hp turbine while the T-72 settled for a 780 hp diesel, but as you can see the advantages in mobility provided by the gas turbine were slim. The difference when driving in tank columns was 2-2.5 kph, an individual tank's technical speed was higher by 5 kph, and during an offensive the difference was just 1 kph! There is no need for any further comments.

1 comment:

  1. That's very interesting article! In terms of fuel consumption of tanks with gas turbine- I have found data from Swedish test which show far worse fuel consumption in Abrams than in Leopard 2. According data- 14.7 liters per kilometer in Abrams and 7.2 liters per kilometer in Leo 2. To be fair, I have found criticism of Swedish data (IIRC lack of APU usage instead gas turbine when tank stay).